This invention relates to program timers and, more particularly, to a drive mechanism for such a timer which has the facility for providing long time intervals at selected locations in the program.
Program timers such as those utilized in clothes washing machines, dishwashers, or other appliances, generally have a sequence control cam drum or disc which is advanced in a step by step manner at timed intervals. The control cam drum, or disc, has various cams for sequencing the program function switches. Generally, the angular steps of the control cam drum range from 4.degree. to 71/2.degree.. Thus, only 48 to 90 steps are available in a complete revolution of the timing cam and obviously only one revolution is available since the programs then begin to repeat.
There is an increasing demand for various programs for different washing cycles. Thus, there is pressure on the timer designer to provide more programs within the 360.degree. rotation of the timing cam. In addition, there is opposing pressure to provide for long soak or delay periods, or the like, which normally consume a considerable number of steps in the timing advance sequence.
It is therefore a primary object of this invention to provide a program timer which is capable of providing long intervals while still being able to provide a number of programs on the timing cam.